When carrying out a surgical operation in which an anterior cruciate ligament substitute is to be inserted in the tibia and the femur it is essential that the ends of the cruciate ligament are fastened so that the attachment locations are isometrically positioned, i.e. so that the distance between these locations, and therewith the length of the substitute ligament, will not change during angular movement of the tibia relative to the femur through O.degree. to about 140.degree..
Many methods have been proposed for determining firstly the precise positions of these attachment locations and secondly the alignment of the holes, canals and the like formed in the bone and serving as guide and/or attachment means for the cruciate ligament. Various instruments and devices for facilitating the alignment and guidance of tools for drilling the aforesaid holes or for forming said canals etc have also been proposed.
A number of these known methods and devices are described and illustrated in U.S. Pat. No. 4,257,411 and in the article "Drill Guides for Improving Accuracy in Anterior Cruciate Ligament Repair and Reconstruction" written by George F Hewson Jr. and published in the journal "Clinical Orthopaedics and Related Research", No. 172, Jan.-Feb. 1983.
The aforementioned known methods and devices are encumbered with a number of disadvantages, however. For example, even though it has been possible to determine the positions of the attachment points with relative precision, it has not been possible to drill holes so that the mouths thereof facing said attachment points coincide with the attachment points, since the holes must be drilled from outside the tibia or the femur respectively. In addition hereto, the holes are drilled in two different working stages, often with the use of two different drill aligning and guiding devices. Moreover, it has not been possible to make the edges of such mouths smooth due to the inaccessibility of the space between the bones.